Stop watch



(No Model.\ 2 Sheets-Sheet 1, E. KUHN.

STOP WATCH. No. 445,064. W Patented Jan. 20, 1891';

gW/TNESSES:

(No Model. 2 Sheets-Sheet 2.

E. KUHN. STOP WATCH.

No. 445,064. Patented Jan. 20, I891.

I '0 r L; /E I I/v I F, fl 4 WITNESSE UNITED STATES PATENT OFFICE.

EDMOND KUHN, OF BROOKLYN, ASSIGNOR TO THE MANHATTAN WATCH COMPANY, OFNEW YORK, N. Y.

STOP-WATCH.

SPECIFICATION forming part of Letters Patent No. 445,064, dated January20, 1891.

Application filed March 21, 1890. Serial No. 344,743. (No model.)

To all whom, it may concern:

Be it known that I, EDMOND KUHN,'a resident of the city of Brooklyn,Kings county, and State of New York.haveinvented an Improvement inStopatches, of which the following is a specification.

My invention relates to that class of watches known as stop-watches, andit consists in a novel arrangement of parts whereby the sweep-secondhandcan be thrown in and out of gear with the main train of the watch, afull description of which will appear in the subsequent part of thisspecification, reference beinghad to the accompanying drawings, forminga part of the same, wherein- Figure 1 represents a plan view of myimproved arrangement of parts when the sweepsecond-hand is held at thestarting-point. Figs. 2, 2, 3, 3, 4, 5, (S, 7, 8, 9, 10. and 11 areviews of the various parts used. Fig. 12 shows a plan view when thesweep-second-hand is rotating, and Fig. 13 a plan view when thesweep-secondhand is at rest after having marked a certain desired spaceof time. Fig. 14 is a cross-section on the lines k of Fig. 12.

In the drawings, A represents the bed-plate of my watch, on which themain train, as well as my improvement, is supported.

At a I securely attach a spring I), having a pawl 61 pivoted at one endthereof and operated by a push-button e. The plate A carries an arborB,'on which turns a ratchet-wheel f and a step-wheel g, both securelyattached to gether. The pawl 61 engages with the ratchet f, and is heldin contact therewith by means of the spring h, said ratchet being heldfrom revolving in an opposite direction by the spring 2'. As theratchet. and step wheel are securely attached together, they revolvesimultaneously. The construction of the stepwheel is shown in Fig. 4 andwhen connected with the ratchet in Figs. 5 and 7. The stepwheel g hasthree sets of steps 1, 2, and 3,0ne of which the lug j of a claw-shapedlever-D is able to engage at a time, the said lever being pivoted to thebed-plate Aat a suitable point i and the lug j held in contact with thestep of step-wheel by the spring m. One arm of the claw-shaped lever Dis constructed on the under side, as shown in the bottom view, Fig.

3, and in section (on the lines o c of Fig. 1) in Fig. 3", and isadapted by the beveled end and short flat surface behind said bevel toride upon the spindle n or any projection thereon and to depress thesame. The other arm 8 of said lever D is adapted to hold the heart-camin its normal position, as in Fig. 1, and to bring it back to saidposition. The arm .9 is on a lower plane than the otherarm of the lever,as in Fig. 14, so that it can strike the edge of the heart-can1. Thespindlen can be united by a clutch 0 o to a driving-wheel F. The outerend of the spindle 12 carries the sweep-second-hand G. The driving-wheelF rotates on a tube 19, surrounding the sweep second-hand spindle a,thesaid tube 1) being adapted to screw into the bed-plate A and bearinga projecting flange (1, above which the wheel F revolves freely. Thewheel Fis held in position by the upper end of the tube 1) being turnedoutward. This wheel F is always in gear with the main train H of thewatch and bears the part 0 of the clutch 0 0, into which the other part0 of said clutch, which is carried by the spindle n, can engage when thespindle n is depressed. The wheel F and clutch 0 0 are shown in Figs. 2and 2 and views of the half-clutch 0 in Figs. 8,9,and 10.

Fig. 11 shows the heart-camE and the spindle n.

The part 0 of the clutch and heart-cam E are held elevatedthat is, intheir normal position-by a spring 0, which operates in a circumferentialgroove in the half-clutch o, as in Fig. 1a.

The operation of myimprovement is as follows: hen the hand G isinitszero position, the claw-shaped lever D enters the deepest step 3 ofwheel g, all as in Fig. 1, the arm 8 bearing on in the recess of theheart-cam E and the spring 7 holding the spindle a raised and the clutch0 0 open. Now, in order to set the hand G in motion, the button 6 ispressed once, thus causing the ratchet-wheel f to advance one tooth andthe wheel g one step, thereby throwing the lug j upon the farthestprotruding step 1,as in Fig. 12. This forces the said lever D upon theheart-cainE and spindle a, depressing both and closing the clutch o o.The clutch nowacts to bring the spindle n into gear with the wheel F andputs the sweep-secondhand into motion. When the desired time has elapsedand the hand G is to be stopped, the button eis again pressed down andthe ratchet-wheel f advanced another tooth, thereby bringing thereceding step 2 of the Wheelg in line with the lugj, as in Fig. 13. Thiscauses the lever D to spring backward away from the heart-cam and allowsthe spring 1' to raise the spindle 'n. and to open the clutch, thusreleasing the sweep-second-hand from the impulse of the train andconsequently stopping it, all as shown in Fig. 13. The third operation,which is to return the hand G to zero, is also accomplished by pressingthe button 6 and forcing the lug j into the deepest step 3 of thestepwheel 9, thus allowing the arm 8 of the said lever D to come incontact with and force the hearteam E back to its normal position, allas in Fig. 1.

The advantages of this invention are its simple operation, itscompactness, and the cheapness with which it can be inanufaet-u red andplaced on inexpensive watches.

Therefore, having described my invention, what I claim is I Thelongitudinally-movable spindle 11, carrying the sweep-second-hand G, theclutchsection 0, and heart-cam E, combined with the spring 0',driving-wheel F, having clutch-section 0 and with the claw-shapedleverD, one arm of said lever being adapted to depress the spindle n andthe other arm 8 bent out of plane with the first arm and adapted to bearagainst the edge of the heart-cam, and with means, substantially asdescribed, for actuat ing the said lever D, substantially as hereinshown and described.

EDMOND KUHN.

Witnesses:

HENRY E.EVERI 1NG, LIVINGSTON EMERY.

